/*#wrap{
        相对定位,限制绝对定位
        position: relative;
        width: 300px;
        height: 300px;
        background-color: green;
        margin: 50px auto;
    }*/
body {
    overflow: hidden;
    margin: 0 auto;
    background-image: url(img/84128-106.jpg);
}

.snowfall-flakes:before {
    content: "";
    /*绝对定位*/
    position: absolute;
    left: 0px;
    top: 0px;
    width: 10px;
    height: 16px;
    transform: rotate(-45deg);
    background-color: red;
    border-radius: 5px 5px 1px 1px;
}

.snowfall-flakes:after {
    content: ""; /*激活伪元素的必要因素*/
    position: absolute;
    left: 0px;
    top: 0px;
    width: 10px;
    height: 16px;
    transform: translateX(4.3px) rotate(45deg);
    background-color: red;
    border-radius: 5px 5px 1px 1px;
}
